This invention relates generally to a process for producing a nitride-hardened surface on a titanium substrate, and more particularly to a process for producing a laser nitride-hardened surface that is highly resistant to cracking.
It is well known to harden a surface of a substrate of titanium by causing nitrogen atoms to be absorbed into a pool of localized molten titanium on the surface of the substrate and to thereafter solidify the molten titanium, to form nitrides in the microstructure. Typical applications require hardness values at least equal to 52 on the Rockwell C scale. One problem with prior art nitride-hardened surfaces of this hardness is that the hardened surface has a tendency to crack upon cooling.
The foregoing illustrates limitations known to exist in present nitriding processes. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming the limitation set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.